Asquare pyramid has a base area of 64 ft the pyramid's total surface area is 224 ft2 what is the area of each triangular face? a. 32 ft b. 53 1/3 ft c. 40 ft d. 160

So you the area of the square pyramid is 224, and the area contains the base area+ 4*the area of triangle surface.
so we can say, 224=64+4*x where x equals the area of each side of the triangle
160=4*x divide by four 
so x=40 ft squared and the answer would be C